This application claims the priority of Korean Patent Application No. 2002-46558, filed on Aug. 7, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a disc player in which a disc cartridge and a bare disc can be compatibly used, and more particularly, to a disc guide device for a disc player, by which a disc cartridge or a bare disc is guided to and correctly placed in a predetermined position on a tray.
2. Description of the Related Art
A disc player is an apparatus for recording onto and/or reading information from a disc shaped recording medium such as a compact disc (CD) or a digital video disc (DVD) using an optical beam. As the density of information stored on a disc increases, recording and reading efficiency of the disc is greatly affected by dust, scratches, or fingerprints on the disc. That is, as more information is integrated on the disc of a constant size, the optical spot irradiated for recording or reading the information is necessarily reduced. Accordingly, recording or reading of information by the optical spot is occasionally disturbed by a very tiny substance or abnormality on the disc. To protect the disc from dust, scratches, fingerprints, or the like, a disc cartridge containing a disc to be rotated therein is widely used as a recording medium for recording multimedia information such as audio and video, etc.
FIG. 1 is an exploded perspective view of a conventional disc player in which a disc cartridge and a bare disc can be compatibly used. Referring to FIG. 1, the conventional disc player includes a housing 10 having a main frame 11 and a cover plate 12 that is assembled onto the main frame 11, and a tray 20, that is installed to move into and out of the housing 10, for carrying a disc cartridge 40 or a bare disc.
A deck assembly 30 is mounted within the housing 10. The deck assembly 30 includes a deck plate 32 typically made of metal, a spindle motor 34 that is mounted on the deck plate 32 and rotates the disc, and an optical pickup 38 that is also mounted on the deck plate 32 and reproduces data recorded on the disc being rotated. A turntable 36 for placing the disc thereon is mounted onto the spindle motor 34. A rear end of the deck assembly 30 is hinged with the main frame 11. A front end of the deck assembly 30 is engaged with a lift device (not shown) mounted on the main frame 11. The spindle motor 34 is mounted near the front end of the deck assembly 30.
In FIG. 1, there is also shown a disc cartridge 40 containing a double-sided disc D for recording information on both sides of the disc. The disc cartridge 40 includes: upper and lower cases 41 and 42 forming a space for containing the disc D therein; center holes 44, that are formed in the upper and lower cases 41 and 42, respectively, and accommodate the turntable 36 and a clamp 14 to be described below; windows 46 that are formed in the connection with the center holes 44 in the upper and lower cases 41 and 42, respectively, and allow the optical pickup to 38 access the disc D; and shutters 48 formed on outer surfaces of the upper and lower cases 41 and 42, respectively, and selectively open or close the center holes 44 and the windows 46. In a case of a single-sided disc for recording information on only one side of the disc, the window may be formed only in the lower case.
The cover plate 12 has a disc clamp 14, for keeping the disc D contained in the disc cartridge 40, or for keeping the bare disc in close contact with the turntable 36 of the spindle motor 32. The cover plate 12 also has an opening lever (not shown) for opening or closing the shutters 48 of the disc cartridge 40.
The disc cartridge 40 or the bare disc is loaded on the tray 20. A disc receptacle 22 is provided on the tray 20 for correctly placing the bare disc. Further, in correspondence with the center holes 44 and the windows 46, respectively, the tray 20 has a center hole 24 for accommodating the turntable 36, and a window 26 that is formed in connection with the center hole 24 and allows the optical pickup 38 to access the disc D.
The conventional disc player as described above additionally includes a disc guide device, by which the disc cartridge 40 or the bare disc is guided to and correctly placed at a predetermined position on the tray 20. In a conventional disc guide device, device for guiding the disc cartridge 40 and device for guiding the bare disc are separately provided.
The conventional device guiding and correctly placing the disc cartridge 40 in a predetermined position on the tray 20 includes a pair of reference holes 58 provided in the disc cartridge 40, a pair of shafts 54 provided on a pair of brackets 52 extending from both sides of the front end of the deck plate 32, and a pair of perforations 56 provided in the tray 20. The shafts 54 of the deck plate 32 are inserted into the reference holes 58 of the disc cartridge 40 through the perforations 56 of the tray 20, respectively, when the tray 20 loading the disc cartridge 40 is moved into the housing 10. To prevent the reference holes 58 from interfering with the circumference of the disc D, the reference holes 58 are provided adjacent to the outer circumference of the disc D. The brackets 52 extending from the front end of the deck plate 32 are required to correctly position the shafts 54 to correspond to the reference holes 58. The shafts 54 are generally made of metal, and are fixed to the brackets 52.
The conventional device guiding and correctly placing the bare disc in a predetermined position on the tray 20 includes a pair of guide holes 64 formed in the tray 20, and a pair of disc guides 62 installed on the tray 20. The disc guides 62 are installed to be above the surface of the tray 20 when the bare disc is loaded. But when the disc cartridge 40 is loaded, the disc guides 62 are elastically depressed through the guide holes 64 to a predetermined position below the surface of the tray 20. The disc guides 62 are provided adjacent to the outer circumference of the disc and the disc receptacle 22 of the tray 20.
FIG. 2 shows operations of the shafts 54 to be inserted into the reference holes 58 in the conventional disc guide device shown in FIG. 1 when the disc cartridge is loaded on the tray. Referring to FIG. 2, when the tray 20 loading the disc cartridge 40 is moved into the housing 10 shown in FIG. 1, the front end of the deck assembly 30 is moved up. Accordingly, the spindle motor 34 mounted on the deck assembly 30 is also moved up to pass through the center hole 24 formed in the tray 20 so that the disc D contained in the disc cartridge 40 is placed on the turntable 36. In addition, the shafts 54 provided on the brackets 52 extending from the front end of the deck plate 32 are also moved up so that upper portions of the shafts 54 are inserted through the perforations 56 formed in the tray 20, and into the reference holes 58 formed in the disc cartridge 40. Thus, the disc cartridge 40 can be correctly placed in a predetermined position.
FIGS. 3A and 3B show operations of the disc guides in the conventional disc guide device shown in FIG. 1 when a bare disc is loaded on the tray and when a disc cartridge is loaded, respectively. Referring to FIG. 3A, when a bare disc D′ is loaded on the tray 20, the disc guides 62 are projected through and above guide holes 64 by an elastic force such as springs 68. As the circumference of the bare disc D′ contacts the side walls of the disc guides 62, the disc D′ is not displaced from a predetermined position, even if the tray 20 vibrates while it is moving. Brackets 66 are provided for supporting the springs 68 under the bottom of the tray 20.
Referring to FIG. B, when a disc cartridge 40 is loaded on the tray 20, the disc guides 62 are pressed down by the disc cartridge 40, thereby compressing the springs 68, and locating the disc guides 62 below the guide holes 64, so as not to interfere with the disc cartridge 40. Thus, correct placement of the disc cartridge 40 is achieved by the insertion of the upper portions of the shafts 54 into the reference holes 58 as described above, referring to FIG. 2.
Since the conventional disc guide device includes separate devices for guiding a disc cartridge 40 and guiding a bare disc D′, the overall structure is complex and numerous parts are required. Further, since the brackets 52 extending from both sides of the front end of the deck plate 32 are necessary for mounting the shafts 54 thereon, the machinery for fabricating the deck plate 32 needs to be sufficiently large to include the brackets 52, and as machinery size increases, manufacturing costs increase accordingly.